| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the generation of any failure even when an access to a graphics controller is generated after control information indicating the transition of the graphics controller to a D3 is set in a configuration register. SOLUTION: A graphics controller 14 is constituted as a device complied with ACPI specifications so that device states D0 and D3 can be supported. The graphics controller 14 is provided with a PCI configuration register to be used for controlling a device state, and when the D3 is set through an AGP 2 in the register, the transition of the graphics controller 14 to the D3 is performed. Moreover, a special mode called a D3 by-pass mode is prepared in the graphics controller 14 as a function for ignoring the setting of the D3 in the PCI configuration register and inhibiting the transition of the graphics controller 14 to the D3.</p> |
